RESUMO
<p><b>OBJECTIVE</b>To investigate the seroprevalence of anti-HAV IgG in adults of 4 cities in China.</p><p><b>METHODS</b>Serum samples were collected from 2390 local residents aged between 20 to 88 years from Beijing, Shanghai, Wuhan and Guangzhou. The anti-HAV IgG in sera was detected with a microparticle enzyme immunoassay (MEIA).</p><p><b>RESULTS</b>The anti-HAV IgG seroprevalence in female of 30 to 39 years in Beijing (64.58%, 62/96) was higher than that in male (45.57% 36/79)) (x(2) = 6.358, P = 0.012). It increased with age in adults of Beijing and Guangzhou. The rates were 54.22 % (90/166), 56.00% (98/175) and 67.18% (88/131) for the 20-, 30- and 40-49 age groups in Beijing (x(2) = 4.76, P = 0.03); and 52.83% (56/106), 52.50% (63/120), 82.46% (94/114), 89.80% (88/98) and 96.77% (60/62) for the 20-, 30-, 40-, 50- and 60-88 age groups in Guangzhou, respectively (x(2) = 72.58, P less than 0.01). This trend was not found in Shanghai and Wuhan (x2 = 0.96, 2.99; P = 0.33, 0.08 respectively). The seroprevalence rates of anti-HAV IgG in the 20 to 39 age group of Beijing, Shanghai, Guangzhou and Wuhan were 55.13% (188/341), 63.93% (429/671), 52.65% (119/226) and 78.37% (308/393), respectively.</p><p><b>CONCLUSION</b>The seroprevalence rates of anti-HAV IgG in young adults aged 20 to 39 years of the four cities are relatively low, and HAV vaccination should be suggested for the susceptible population of this age group in China.</p>